Studies on larger animals, in particular weanling pigs are to be initiated as a first step toward the development of capabilities for biomedical studies in larger animals and for future clinical uses of EPR. Emphasis will be on the development and testing of the instrumentation. These include testing resonators, developing physiological monitoring methods during the EPR studies, studies of larger animal models, use of India ink to measure oxygen at or near the skin. Initial clinical studies will focus of EPR oximetry in cooperation with the clinicians at the Dartmouth-Hitchcock Medical Center with the objective of demonstrating feasibility and the value of such studies. They will use the least invasive methods.